Halakhah for Yevamot 43:6

And [it] is practiced in all places and at all times by males and females, and so [too,] by [those the sex of which is in doubt]. And a child of unknown paternity is obligated towards his mother, but he is not obligated towards his father, even if his mother was questioned and she said that he is the son of x. And it appears that a mamzer is liable for cursing his father and his mother - as behold, he is fit to inherit them from Torah writ. And he also has the status of a fit son regarding mourning and for everything. But the son of a female slave or of a gentile woman is not liable for their curse. And so [too,] a convert whose conception was not in holiness - for example, if his mother converted when she was pregnant - is not liable for cursing his mother. And just like he is not liable for cursing his father, so too is he not liable for cursing his mother, even though she was Jewish when she bore him; and like they, may their memory be blessed, expounded (Sifra, Kedoshim, Chapter 9:9), "'And he who curses his father and his mother' - one who is obligated for his father, is obligated for his mother, etc." And it should not be asked about this teaching based on the son of unknown paternity who is only obligated for his mother - as [there] the father is not known and recognizable. And a convert is rabbinically forbidden to curse his gentile father, so that [people] not say he came from a stringent [level] of holiness to a light one (see Yevamot 22a). But a slave has no lineage, and behold his father is like someone who in all respects is not his father - and even after he is freed. And one who transgresses this and curses them with one of the names [of God] is stoned; and that is when there are witnesses and a warning there - as is well known in every place. But if he [only] curses them with one of the appellations [of God], he is lashed.